Seagulls commandeer abandoned ship, bomb Launceston businesses

Two of Launceston's biggest retail buildings - Bunnings and The Good Guys - have been among the hardest hit, and there are concerns that the booming seagull population could pose a health hazard to the community.

Launceston businessman Errol Stewart, who has helped develop much of the land surrounding the problem site, said the birds had become a big problem.

"They're just an absolute pest," Mr Stewart said.

"Bunnings is absolutely covered in seagull crap, as is the Good Guys, as is our aircraft hangar - you put a car over there and it'll be covered with seagull crap in 10 minutes.

"The Good Guys store has got significant solar panels on the roof and instead of being black they're white.

"I don't know what the solution is, but they're a problem."

Authorities have been working for more than five years to stop silver gulls nesting on the derelict Harry O'May, which is tied up opposite Tamar Valley Dairy.

Once a car ferry servicing Bruny Island, the vessel has become home to huge numbers of seagulls, particularly around the August breeding season.

Birdlife Tasmania convener Dr Eric Woehler said the vessel provided an ideal hang-out for the "opportunistic" gulls, which are a protected species.

"It's a convenient nesting platform, but it's also close to the Mowbray tip, so you have food close by as well as a safe nesting spot," he said.

"Because there's water between the ferry and the shore - even at low tide - it means the wreck is basically free of predators.

"So the birds can nest there without the threat of predators taking adults or chicks."

Dr Woehler said groups of seagulls were roosting on ground sites - such as a vacant block near Invermay McDonald's - as well as atop large buildings.

"It's simply a reflection of an increased local population making its presence felt by roosting on rooftops and elsewhere around the city," he said.

The Harry O'May is one of several ships that have been left rotting on the Tamar River for decades.

The Examiner revealed last week that legal action is under way concerning four abandoned vessels, including the Harry O'May, as authorities attempt to clean up the waterway.

It remains unclear if, or when, the ships will be moved.

Dr Woehler said it was hard to predict how the gulls would respond should the Harry O'May be relocated, including whether they would stop roosting at Bunnings.

"It's likely... the distance to the nearest food supply would be part of the decision that the birds make as to whether they persist or not," he said.

In the meantime, work continues to dissuade birds from nesting on the ferry.

A range of experiments have been tried in the past five years - periodic loud noises, citronella repellents, moving string lines, and human and drone disturbances - but none have proven successful.

Since early 2022, the Department of Natural Resources and Environment has engaged CSIRO to see whether pre-August laser lights would keep gulls from nesting on the ferry.

The birds acclimatised to the lights within 24 hours of both trials to date, but researchers aren't giving up yet.

"We are currently in the process of revisiting the design of the lasers by updating the frequency and rapidity of movement," CSIRO environment research scientist Geoff Tuck said.

"Additional deterrents, notably sound-based interventions, are now being considered as we endeavour to devise a more effective deterrent mechanism."

Easy fixes have proven hard to come by for Launceston's seagull boom and shipwreck collection.

But if the new laser design works, it could help solve a problem experienced all across Tasmania.

"Considerable time and financial resources are dedicated to the removal of gull droppings from essential infrastructure across Tasmania, including various businesses and marinas," Mr Tuck said.

"While acknowledging the financial burden incurred by these businesses, we are also aware of the need to minimise disruption to the birds."